


symbiotic.

by TheBookDinosaur



Category: Harry Potter - J. K. Rowling
Genre: Community: HPFT, Tom Riddle has a twin sister AU, it's amazing how many words i've written for this and i still flail hopelessly trying to describe it
Language: English
Status: In-Progress
Published: 2016-04-09
Updated: 2016-04-09
Packaged: 2018-06-01 04:33:49
Rating: Mature
Warnings: Graphic Depictions Of Violence, Major Character Death
Chapters: 5
Words: 19,110
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6500986
Author URL: https://archiveofourown.org/users/TheBookDinosaur/pseuds/TheBookDinosaur
Summary: <blockquote class="userstuff">
              <p>Tom and Stella Riddle showed the world a united front for so long that they almost forgot there were any other options.</p>
<p>When they started to compete, they couldn't really stop.<br/><i>an AU</i></p>
            </blockquote>





	1. i. the beginning {or} the foundation stages

**Author's Note:**

  * For [sideraclara (angeloscastiel)](https://archiveofourown.org/users/angeloscastiel/gifts).



> elisabeth: you are one of the best friends i could ever have asked for and im so glad that shared wailing brought us together. i had the idea for this ages ago and only just started writing, but it was always going to be for you ♥

**i.**  
It is raining when they are born, clouds the colour of bruises steadily releasing torrents of rain. The droplets beat out a pattern on the roof, water sliding down the windows and smearing the already-bleak view, and Merope Riddle sits in front of a fire, hands held out in front of the flames, trying to avoid looking at the babies she has just given birth to, because there is no way she will ever be able to provide for them and she will not grow attached to babies she will only leave behind.

Still, she cannot help sneaking glances at them out of the corners of her eyes as the midwife rocks them, one held snugly in each arm. It does not take her long to observe that they are polar opposites. He is dark-haired and she is light, he is large for a baby and she is small. His hands wave around wildly, she is still. Her eyes are open, his are firmly closed.

There is only one similarity between the two of them, and that is their silence.

“Tom,” Merope says as she stands up. Her eyes are hollow. There is blood staining her filthy dress, but it’s hidden among the multitude of other questionable stains that the material is already holding. “Name him Tom Marvolo Riddle.”

She doesn’t like to think of it, but – Tom because she loves him, loves him so much that it aches, still, even after he had left her. Even after he had broken her heart it was beating for him.

“And the girl?” the midwife asks, holding the small bundle gently. 

“I don’t know,” she says. She has no sister, no aunt that she knows of to name her daughter after. She doesn’t even remember her mother’s name. “Something nice. Something pretty,” she says. “Not Celia,” she adds, thinking of the woman who she’d heard had married Tom, who had ruined her life, who’d stolen her Tom away from her. There is a pause in the small room, and the midwife looks down worriedly at the babies in her arms as their silence persists.

There is a well-built woman sitting in the corner of the room, where she has stayed throughout the birth, looking out of her depth and being a little useless. “Will you be taking them with you?” she asks now.

Merope has to shake her head, and she can feel her heart breaking all over again.

“I’m sorry,” she says in a whisper, “I have nothing. No money.” She slips out of the door before the imposing woman can demand something of her like physical labour, which she knows after a lifetime of blunders that she is terrible at. The hall is dark, and the front door has been left open.

“What’ll we name her, Mrs Cole?” she hears the midwife ask, and pauses in the hallway. This is something she wants to know.

“I don’t know,” Mrs Cole says, sounding remarkably harried. “Something pretty – Stella,” she says in a firm tone. “My sister was named Stella.”

 **ii.**  
Tom and Stella, then, grow up together, closer than any other brother-and-sister pair that Mrs Cole has housed, although she attributes this fact to them being twins. Being in the womb together might have caused a psychic connection, or something, she supposes.

If she’d looked closely, which she didn’t, she would have seen that the difference of hair colour was misleading – she would have seen their almost identical noses, their shared delicate jawline, the matching shape and colour of their eyes.

As it is, she finds it sort of sweet that they are always together; sitting next to each other at meals, during outdoor hour, during lessons. His gleaming dark head is never far from her angelic blonde curls; they are always together, always quiet, the only ones talking in whispers while the other children are screaming and shouting and carrying on. They are never the ones making any sort of fuss, for which Mrs Cole is profoundly grateful. They seem to prefer corners where they are more difficult to spot, and they are so rarely seen apart that they’ve become two parts of a whole in Mrs Cole’s mind, Tom and Stella becoming TomandStella. She can hardly imagine them without each other.

(She is, of course, kept in the dark regarding their free-time activities, vaguely assuming that they continue to sit in corners and talk to one another in mutters, and Tom and Stella take a sort of gleeful pleasure in keeping her so thoroughly clueless, so convinced that because they are quiet they are no trouble.)

“A mouse,” Tom whispers to Stella. His pale hand grasps her wrist through her dark sleeve.

“I know. I can see it,” Stella says, taking his hand, and watches as Tom’s face grows serious, watches as he stares at the mouse with a singular intent written all over him that she has never seen come out in anyone else.

The mouse moves, squeaking, towards the rotten cheese in the mousetrap that was all the kitchen had to spare for traps, rotten cheese that should not under any circumstances have appealed to it in the slightest.

Tom does not speak, but his eyes are bright and focused, and there is a half-smile on his face that says more than words ever could.

Stella watches him with a matching half smile on her face as the unfortunate rodent steps on the wrong board. It happens in an instant; the board, coming down to trap the mouse, the loud snapping noise, the terrified squeaking. The sudden silence.

She knows what comes next, what almost always comes after one of them have managed to do yet another thing that cannot be explained away. “It’s _insulting_ ,” Tom complains as he glares at the mouse in the trap, like it’s the mouse’s fault, his face twisted into a bitter scowl. “To know that she thinks we’re beneath her. If she could see what we could do –”

“She’d probably send us to the asylum,” she finishes his sentence, even though she knows that wasn’t what he was going to say. “We don’t want that, Tom.”

He grumbles, as he always does, but her quiet reason overcomes his need to be acknowledged, and he comforts himself by doing more and more behind Mrs Cole’s back, doing more and more to prove that he is better than her.

 **iii.**  
Neither Stella nor Tom understand how the others at the orphanage _think_. Their thoughts are always almost identical, so close that they can practically tell what the other is thinking. Tom doesn’t understand why dead things – mice caught in traps, flies against the windowsill, rats dead of starvation – make people scream so. Stella doesn’t understand how they don’t grab at the chance to learn more about bodies when they have the opportunity. She has taken these chances with a wide-open mind, taking small, fragile bodies apart with quick and delicate movements, because she doesn’t think that she will ever know enough; she knows that blood is red and bones are attached to other bones, and that a body is made up of such a complicated system it is beyond belief.

“Stella,” Tom says, in a whisper, “come look what I did.” She rises and follows him through the halls as the pre-dawn grey starts to lighten the sky. “I can make animals do things,” Tom says, an excited gleam in his eyes that looks almost mad as they tiptoe down the corridor, avoiding the squeaky boards with an ease borne of long practice. “Stella, I can make things do _anything I want_.”

“I know, silly,” Stella says, looking up at him. “I know that.” Tom shakes his head, and the boards creak under his feet as he loses concentration for a second. Stella freezes, but Tom pulls her along.

“Stella, this is different,” Tom says, restless. She wants to put out a hand to stop him, but lets him continue walking as the wooden boards creak under his agitated feet.

“How? What did you do?”

“I made Billy’s rabbit hang itself,” he says, his tone still disbelieving. “I made an animal _hang itself_.”

“Did you get it to tie the knots too?” Stella asks, and Tom scowls at her for dragging him back down to reality.

“I tied the knots. Stella, this – this is amazing. I’ve never done anything like that before –”

“How is it different to making mice walk into traps?” Stella asks. Tom shakes his head.

“I used the cheese as bait,” he says. “All I had to do was convince them that the cheese was delicious and they did the rest. I’ve never just – _made_ them do something, even if they didn’t want to, just by thinking it.”

She’s saved from having to think of a response as he pushes the door to the courtyard open and they step onto the dewy grass. As her feet grow colder, Stella is arrested by the sight of the dead rabbit, hanging off the roof. It’s swaying in the wind. “Tom,” she says accusingly, swatting his arm. “You just left it there?” She shouldn’t be surprised, since he wouldn’t have wanted to show her anything other than the feat in its original form, but she can’t help but think of the others’ reactions. He shrugs, careless, looking up at it with something like pride in his eyes.

Stella glares at the dead rabbit, and it shimmers briefly before fading, a little, so that it’s a little bit transparent. This time it’s Tom who swats at her arm. “Stop that,” he complains, because he doesn’t want this triumph to just disappear. “Leave it. Nobody’s going to suspect us.”

“They’re going to wonder how a rabbit got up there to hang itself, though,” Stella says, glaring at him. “They might think that you did it by hand.” Tom rolls his eyes, but doesn’t protest as Stella glares intensely and the rabbit slowly fades from view until all that remains of his feat is an innocent length of rope, wrapped in tight knots, tied to the rafters and still swaying.

 **iv.**  
Stella’s skills develop differently from Tom’s. Tom can make things do what he wants them to. He invades their mind, exercises absolute control, even when their minds resist him. She can manipulate the physical objects of things, levitating blankets and causing flowers to bloom in the middle of winter. She can refill a glass of water or a bowl of porridge, and she can, with enough effort, make a thing disappear. She hasn’t mastered making them appear, though.

Tom is unhappy with this set of skills he cannot compete with, and so he learns parlour tricks and sleights of hand, to make himself even. He finds a set of cards somewhere and makes her laugh as he shows her the card that she picked, every time; he pulls roses out from behind her ear and makes balls fly between his fingers. He even learns to juggle for her, and then has to learn to evade her swatting hands.

She responds by observing everyone in the orphanage, and wonders why nobody can think properly. She watch as children break down and cry, or scream, and note exactly how it happens. She wields her words like weapons and proves to Tom that his mind-gifts aren’t necessary when she can watch and observe and catalogue and know exactly what to say to make people to smile, what to do to make them cry. “Hurting them without touching them,” Stella says to Tom as they sit together on the back staircase. He nods, and grabs his little brown ball from behind her ear.

It’s a new feeling for Stella, and one that she pokes at and prods at like one would poke and prod at an unexpected new finger or toe. She is so used to presented a perfectly united front to the others at the orphanage and Mrs Cole that she has barely realised there was another option. 

Being competitive, striving for her best, always trying to prove herself the better, not having to hide what she can do from at least one person – it is all a breathless relief. She decides, after a little contemplation, that she loves it, which is good, because Tom feels exactly the same way.

 **v.**  
The door to the orphanage opens and Mrs Cole comes into the room, gabbling on about something, twisting her hands in her apron, eyes darting around the room to make sure that it’s clean enough. Following her is a stately lady with a lace-trimmed umbrella and a full skirt. She looks around at her grimy surroundings with contempt on her face, but waits without a word as Mrs Cole rings the bell which calls all the orphans down to the front hall, and children materialise out of every nook and cranny.

“We’d better go,” Stella says when Tom doesn’t move. He glares at her, and she returns it. “The lady might not notice, but Ms Cole will, and you’ve a good chance of not being picked. I think she wants a girl.” She has been right nearly every time, predicting what kind of child a visitor wants.

Tom is still for another moment and then he heaves himself up, fixing a rebellious expression on his face and slouching. Stella reaches over as he starts to descend and ruffles his hair to help him appear like a Bad Choice. “Don’t get picked,” Tom says, his voice low, as they come into the room with the stragglers.

“I know,” Stella says. They squeeze each other’s hands at the same time, and smile at their perfect similarities.

She joins her place in the girls’ row, and observes how desperate each of the others are to be picked. Their faces have been hastily washed, and some of them have slapped each other to bring colour to their cheeks. Their hair is done perfectly, ribbons tied neatly, dresses smoothed down with anxious hands to the point of almost ripping the thin material. Stella slouches, allows her dress to wrinkle, makes sure that her ponytail is as sloppy as she can make it. The other girls look at this lady-visitor with awe and desperate hope in their eyes, and Stella doesn’t blame them, but she will not be adopted without Tom.

She’s right about the lady visitor, as she is so often; the lace umbrella makes its way down the row next to its mistress, facing the girls and ignoring the boys, hard blue eyes scrutinising every fault. Stella is more than prepared to pour resentment and rebellion into her eyes, but it’s not necessary. The lady-visitor barely spares her a glance before carrying on down the line and choosing another girl who looks to be the very soul of obedience.

Tom meets Stella’s eyes, and both of them smile.

 **vi.**  
There is one all-important day where everything changes, and Stella will remember the thirty-first of October in her eleventh year until she dies.

A tall man with a great, splendid head of orange hair and an equally orange beard comes to visit the orphanage. Tom and Stella are sitting on the back stairs when he comes in, and both of them tense a little, ready to make their way through another evaluation, ready to fail another test.

Tom is even more tense than usual. “There’s something different about him,” he says, softly, taking her hand. “He’s different.”

Stella has opened her mouth to disagree, and point out that perhaps the man’s head of fire-hair has blinded Tom, but then the visitor turns at the staircase and peers up towards them. He should only be able to see a half-definite shape in the gloom of the staircase, but his bright blue eyes meet Tom’s, and then Stella’s, and he winks at them. Then he’s whisked into Mrs Cole’s office and out of sight.

“He shouldn’t be able to see up here,” Stella says, and she won’t admit it in so many words but she’s spooked. “We tested this. It’s too dark.”

“See?” Tom asks. “Different.”

“I don’t like him,” Stella decides. Tom shrugs, and she knows that this unusual man fascinates him.

When Mrs Cole comes out of the office, something is wrong with her, too. Her eyes are slightly unfocused and she is swaying a little on her feet. If Stella had to guess, she’d say that Mrs Cole had been drinking, but even a whole bottle doesn’t affect her this much, and Mrs Cole would probably die before embarrassing herself by drinking in front of a visitor.

As though her thoughts summoned him, the man with orange hair stepped out of the room behind her, fiddling with his sleeve. Mrs Cole grabs a passing maid by the sleeve and tells her in a slurred, drunken voice that the visitor wanted to see Tom and Stella. Stella tenses, and beside her Tom does the same.

“I’ll go to them,” the man says, and Tom and Stella barely have to look at one another before turning around to race up the stairs and into their shabby little room.

He joins them a minute later, without a maid, presumably having navigated the halls and corridors himself, even though he should by all rights be hopelessly lost and somewhere in the kitchens by now.

“Hello,” he says, when both of them stare at him gormlessly. They hadn’t even needed to talk to one another to agree on their act; they would be quiet and overawed by this man, who carried himself so confidently. “My name is Albus Dumbledore.” 

He finds words to explain to them about a school of magic, a special school for special people where he is a professor. Stella asks him, quietly, to prove it, and tells him that she won’t be tricked into going to an asylum. Tom squeezes her hand and almost, almost shouts out as their closet bursts into white flames with a wave of a stick – she can hear the shout rising in his chest, choking at the back of his throat. When the closet re-emerges from the flames like a phoenix, perfectly unburnt, Tom’s façade of dullness slips, and a wild, bright excitement shines on his face like a beacon. Stella purses her lips.

“I knew we were special,” Tom says, “I knew we were different.” He tells Professor Dumbledore about hanging a rabbit, and Stella can see that the stranger disapproves, but that he knows how to hide it. She still doesn’t trust him.

The stranger takes them shopping, to a place that is signposted as _Diagon Alley_ , and Stella can barely keep her eyes inside her head, there are so many strange and wonderful things around them. He buys the two of them books and potioneering equipment and wands like his own, and Stella cannot bide her delight when he tells her that the library at Hogwarts is a hundred times larger than this bookshop, which is of a not-inconsiderable size. Still, she feels like he’s watching her throughout the trip, assessing her and Tom, and she knows that Tom feels it too because he is too quiet, too reserved. Truthfully, she is glad for his reticence, glad to know that he is only fascinated and not bewitched with this mysterious stranger, because it means she’s not alone in her constant suspicious.

Professor Dumbledore tells Mrs Cole to take them to Platform Nine at King’s Cross Station tomorrow morning by eleven sharp, and she nods blurrily, peering out at him from bleary eyes. “They’ve been chosen to attend a very selective school,” he tells her, and she smiles and says something incomprehensible which is presumably encouragement to adopt them. “They’ll only need to come back over the summer, although they can join you for Christmas and Easter if you wish.”

He takes his leave of the orphanage soon after that, and Tom and Stella watch him walk away from the window, holding hands tightly and contemplating this sudden and alarming new future that has opened up in front of them.

 **vii.**  
The next day is the stat of a new month and it is so full of new and exciting discoveries that it’s also vaguely terrifying. Stella has always been so sure of where she stands in the orphanage, she and Tom know every nook and cranny and secret little space. They’d thought it was boring, that the knowing of a place caused it to become dull, but she thinks that maybe it only meant that the place was familiar and a little too comfortable.

“Don’t worry,” Tom says, even though she is trying to keep a straight face, because he can read her as well as she can read him. The two of them are mostly being ignored on the platform, although ever since Mrs Cole has left they are being the recipient of more and more quizzical looks because they are two children without a chaperone on a busy platform, with large trunks by their sides.

“I’m not worried,” Stella lies. Tom starts walking towards the boundary between the two platforms and she keeps pace with him, half because she doesn’t want to be left behind and half because the familiar warmth of wanting to be the best demands that she beat him to the platform nine and three-quarters Professor Dumbledore told them about.

Both of them cannot help closing their eyes as they pass through the platform, and they find each others’ hands; when they open their eyes again, both of them are arrested at the sight of the scarlet steam train, shocked to a standstill so that they are nearly bowled over by the next person to come running through the wall.

“This is _exciting_ ,” Tom says, and Stella can feel her heart beating out a wild, erratic rhythm against her ribs.

“It is,” she agrees, and they turn to smile at one another.


	2. ii. the building-up {or} the starting gun

**viii.**  
Hogwarts – well. Hogwarts is nothing short of a revelation. There are so many people, so many stones, so many books – the school is a place of extremes beyond imagining.

The teachers seem to enjoy pitting students against one another, encouraging the competitiveness in class and enjoying the improved grades this leads to.

Stella and Tom somehow manage to find a way to combat this because they want to continue showing their united front, their perfect, flawless charade. Their system is one with checks and balances and careful, careful machinations, because behind the façade they are constantly trying to tip the balance towards themselves, just a little.

To the world, Tom is skilled in Potions, where he learns all he can about each individual ingredient, how they react and what they effect, experimenting with them during class time to the annoyance of the teacher, whose irritation quickly morphs into delight as the fruits of Tom’s labour result in perfect potions. He teaches himself the History of Magic and, more importantly, the history of people. He maps the stars and excels in Astronomy. The teachers come to know him as the boy who is always in the books, surrounded at all times by the smell of parchment and pages. Inkstains linger on his fingertips.

Stella is given the practical subjects, and she excels in them. In Charms, she learns that the oral aspect is the most important in casting a spell, and learns to control her voice flawlessly; how to set the pitch and tone of it, to cast spells and to talk to others. In Transfiguration, she is taught that the kinetic is the most important aspect in casting a spell, and learns to manipulate her own body movements faultlessly, always applying the perfect gesture at the perfect time. She fights in Defence Against the Dark Arts, and finds a certain comfort in the fact that she can manipulate even magical creatures if she puts her mind to it. She learns to control and care for plants in Herbology, determined that she will be able to control everything in her environment. She tries to dig the dirt out from underneath her fingernails, but bits of them are always stubborn, always remain stuck.

But when they are together, and there are no teachers and no nosy students – they equal one another in everything. Neither of them know how long they can do this, how long they will be able to keep up with the pace they both set, but for now this is enough.

 **ix.**  
Stella finds herself, often, amongst the tall shelves which carry volumes documenting the human body. She can barely believe what she sees, what the Healers and muggles have found out, and thinks that perhaps she has found something which is more complicated than her push-and-pull with Tom. She reads about blood travelling through the tiniest veins, or the largest ones; hormones and chemicals and reactions of the body. She learns about the all-important beating of the heart, the all-important pressure of the lungs, the all-important strength of bones. There are so many things which are all-important in the makeup of a body that she can hardly believe there are so many people alive and walking around. The human body is made up of such a complicated system that she can barely comprehend how it came to be.

Tom doesn’t truly like this fascination of hers. “There’s no point learning so much about a body,” he says, when they are twelve and have returned thankfully, gratefully to Hogwarts after suffering through a summer at the orphanage, and she has made a beeline for the books on anatomy. “Not when you can learn about their minds.”

“Sometimes you can use bodies to manipulate minds,” Stella says, even though she doesn’t really understand her own argument and Tom knows it.

“That doesn’t make sense,” he says, challenging her to come up with another, better argument. She tilts her head to one side.

“You know how not to kill things,” she says at last. “If you want something, and they won’t give it. You know what to do to hurt and not kill.”

“What happened to hurting them with words?” Tom asks, but she has planted a seed in his mind and the next time she is sitting among the dusty old shelves he sits down next to her and leans his head on his shoulder, reading as she reads.

“You can do both,” Stella tells him, and she can feel his nod against her shoulder.

 **x.**  
In her defence, what she will always use as a defence against prying questions and questioners, is that Tom _started_ it. She fought back because if she hadn’t he would have taken it to mean weakness and then taken advantage of her. Or, that is what she resolves to tell anyone who asks, much, much later.

The truth is that neither of them start it – or, one of them started it because one of them had to, but Stella doesn’t know when exactly and how exactly and why exactly and who exactly. Maybe it started when she gloated about levitating an entire mattress to him, or when he learnt to juggle because she couldn’t. Maybe it started with his stupid sleight-of-hand tricks, or her manipulations of the other children. Maybe it was a race they were made to run from the moment they came into the world. Maybe they were made this way, crafted so that there was only one, inevitable, outcome.

She is thirteen when Tom first tries to kill her.

“I’m finished,” he says, rolling up his map. They are not in the library as they usually are when they study, but in the middle of a clearly abandoned corridor, leaning against the railing of a staircase. Smugness seems to radiate from him, and of course she takes the challenge.

“No, you’re not,” she says. “You forgot Jupiter’s twelfth and thirteenth moons. I was watching.”

“Is that why you’re so slow? You’re watching me work? _Star_ ,” he says sarcastically, faux-disappointed.

“Star?” Stella asks, making a face. He makes one back.

“Stella the name comes from Star the word.”

“I know that,” Stella snaps. “It doesn’t change the fact that your planet chart is wrong.”

“It’s _fine_ ,” Tom says, his voice angry, and his hand flashes out and pushes her down the stairs. It is a terrible amalgamation of feelings – she can feel a sick sort of pop in her shoulder, a crack in her leg. She can feel her brain clamouring, saying that _no, no, it’s not meant to be like this_. Her teeth find her tongue, and the impact on her head is so strong that all of a sudden her mouth is filled with blood. She curls up when the stairs finally spit her out, when she tumbles to the bottom and stays there with a bone-jarring finality.

Of course Tom comes down after her, and of course he brings her to the Hospital Wing with a look of frantic worry etched perfectly on his face. Madam Gilfour tuts and pokes around with a hand that is really not as gentle as she thinks that it is.

“I felt something in my shoulder,” Stella says at last, lifting her head, not meeting Tom’s eyes. She doesn’t want to go through any more of this heavy-handed inspection. “And my leg, and my tongue.” She puts a pained smile on her face. “It was my own stupid fault,” she says. “I tripped over myself.”

Madam Gilfour shakes her head and looks displeased with this answer, tutting as she heads over to her storeroom. Stella watches her go, schooling her face into the perfect impression of blankness before turning to face Tom.

“Hope you’re happy,” she tells Tom, and makes her eyes flinty and hard. She hopes that he can read the message she’s sending him – _you can’t win_. He smiles at her, a true smile, and takes her hand as Madam Gilfour comes bustling back and Stella puts a faintly pleading, suffering mask on. Her tongue is still bleeding, just a little, and Madam Gilfour tuts in the way she has and gives her potions to heal the cut.

Stella is glad that her teeth found her tongue, although she will never say it to anyone. If her tongue and teeth hadn’t been otherwise occupied, she might have screamed as she went tumbling down those stairs and that would have been humiliating beyond measure.

Madam Gilfour tells Stella sternly that she is to stay overnight and not exert herself in the next three weeks in any way. She also lets Tom stay after he asks so politely, even though visiting hours are over because they _are_ twins, and then she hurries along back to her office where there are presumably Important Things waiting for her.

“I don’t know how I’d live without you, Star,” Tom says once quiet has settled over the room, and she doesn’t really mind his use of the new nickname. “I don’t know how I’d move.”

Stella longs to say something which would elevate her, something like _you couldn’t, Tom, not without me_ , but there is no point in that and so she squeezes his hand, just a little, and says, “With your body.”

xi.  
Professor Dumbledore comes to see her, in the hospital wing. He says that he’s only here to check up on his best student, but she can see something else behind his eyes and doesn’t quite trust him.

“I should be fine by tomorrow,” Stella assurers him. Tom is still by her side, holding her hand, and he avoids Professor Dumbledore’s gaze.

“I’d just like to hear what happened, if you don’t mind my asking,” Professor Dumbledore says. “If there is anything I can do within the castle to avoid something like this happening again –” he breaks off, delicately, and it’s a perfectly reasonably excuse but Stella doesn’t trust it, doesn’t trust him.

“Oh, no, it’s not the school,” she says with barely a pause in the moment. “No, Tom and I had finished our homework and we were walking back to the common room and he said something, and I was laughing and not looking where I was going, and so it really is my fault.” She looks down at the end, like she’s ashamed or embarrassed as such carelessness, and lets the blood rise to her cheeks.

“I wish you a speedy recovery then, Miss Riddle,” he says finally, and takes his leave of them.

“Do you think –?” Tom asks.

“I doubt it,” Stella says.

 **xii.**  
Whenever he touches her, she moves, suddenly and against her own permission, flinching away from her brother. Her mind is all too happy to forget about or revise what had happened but the muscles and bone and tissue in her body still remember the sick popping noise, the way her teeth sank into her own tongue, the way her leg looked to her as the cold stone floor had sucked all the heat out of her small body.

“ _Stop_ it,” Tom says, shoving her into a desk when he gets tired of her flinching away from him.

“I’m _trying_ ,” Stella snaps back shortly.

But the thing is, she can’t. Her body remembers, vividly, how it had felt to go tumbling down those stairs, and she’s not scared of him, she truly isn’t, but her body just can’t let the fall go.

The next day, in the cold dampness of the dungeon, Slughorn announces to them that as a revision activity they’re going to be brewing the Draught of Living Death. “You should be able to do this without partners this time!” he says happily, beaming around the dark little room and looking immensely out of place for it.

“When he says ‘revision activity’,” Tom murmurs to her alone as they move into the storerooms to gather their ingredients, “he means that he forgot to prepare a lesson plan and doesn’t have the brainpower to improvise.”

“Well, not everybody can be as resourceful as you,” Stella says. Almost of its own accord, her hand moves up the shelves and, with a quick look at Tom to make sure that he’s occupied with picking out his own ingredients, she grabs a small, easily recognisable jar of ground turtle shell and another one of snail shells that she hadn’t even realised she’d seen until they were in her hand.

She regards them carefully once she gets back to her desk, hiding them from Tom’s sight with the rim of the cauldron. She knows what this will do, what it will cause the Draught to become, and slips the glass jars into separate pockets to avoid clinking.

Her Draught is carefully, calculatedly not quite as perfect as Tom’s potion, but she makes sure that her errors make the potion more susceptible to last-minute additions. She bottles a vial of the potion and sets it aside quietly before putting just a pinch of both stolen powders into her potion. She thinks of her fall down the stairs, thinks of the sudden, flashing pain that she had felt in her shoulder and leg and tongue, and the bruises that had appeared on her delicate body. She has to fight the triumphant tilt to her smile as the potion darkens just a little, swirls more slowly, the smoke rising more sluggishly.

She bottles a vial of this as well, and Vanishes her potion silently as she brings the first vial she’d bottled up to the professor. “Well done! A good effort, Miss Riddle – next time be a little lighter with the asphodel root, hmm? Get your brother to help!” he laughs as Tom comes up behind her. She slips away quietly as he begins to heap praise onto Tom’s perfect potion.

The weight of the potion in her pocket seems to drag her robes down, and Stella thinks she understands why she defended Tom in front of Dumbledore. She had puzzled over it while she should have been sleeping – admitting that Tom had pushed her down the stairs was out of the question, of course, because as much as she ached all over she didn’t want him punished too harshly, didn’t want any stain on his reputation. But there had been nothing stopping her from saying that, oh, Tom had been a little careless with a spell, or tripped her good-naturedly and accidentally sending her down the stairs. He would have been punished for carelessness if nothing else and she had entered a dozy, fitful sleep in the small hours of the morning without coming to an answer.

Now, she thinks as her hand curls around the cold glass vial in her pocket, she has her answer. Reprimanding Tom, making him know that she was off limits; it was something she needed to do personally. She didn’t want authority figures getting in her way.

 **xiii.**  
She does it at dinner that night, because there really is no point waiting. She distracts Tom briefly, pointing out someone who comes into the Hall and repeated a rumour she’d heard about them; when Tom turned back to his food after searching the Hall for them, she’d poured the potion in and it was done. The wheels had been set in motion.

He doesn’t feel the effects until after dinner.

“I feel funny,” he says. The muscles in his neck strain as he tries to lift his arms and only manages to get them above his knees. “Star –”

“Are you okay?” she asks, concerned, lifting his hands. He can’t keep them up in the air, though, and they drop back to his knees. She stands up and guides him up as well, putting her arm around him as she leads him outside and towards the hospital wing, sending their stuff back to their dorms with a wave of her wand.

“Something – numbing,” he says, leaning so heavily against her that she almost stumbles before catching herself. “Stella –” he says, and the muscles in his jaw clench and unclench as he tries to keep control. “You haven’t let me be this close to you since –”

“Well, you do need my help,” she says, cutting him off because she doesn’t want to talk about it, not now. He mumbles something unhappily, and his hand on her arm twitches. She waits until they are alone in a wide corridor with no paintings as witnesses to talk, and this is the reason she’s so close to him; it is more chilling for him to hear this from her as she is nestled into his side compared to if she was levitating him across the corridor. Everything is calculated. “Your arms will sleep first. Then your feet, then your legs. If you don’t get an antidote soon enough your brain will sleep as well, and you will die because your heart and lungs will stop.”

He looks down at her, and there is something in his eyes that makes her think of herself, down at the bottom of the stairs. “You –” he says through laboured breathing as they approach the hospital wing. “Poisoned me.”

“Yes,” Stella agrees, her voice pitched low enough so that only he can hear even as she twists her face into a mask of worry. “How does it feel, Tom?”

His face twists into a smile as he stumbles, stomps his feet and cannot feel them. He is saved from having to reply by Madam Gilfour, who practically runs out of her office when she sees them.

“I don’t know what happened!” Stella cried out, her voice high and frantic with worry. “It was after dinner, and he just – he was just –”

“It’s alright, Miss Riddle,” Madam Gilfour says, guiding Tom to a bed. “Do you know what happened?” Stella shook her head and allowed tears to come to her eyes; from the bed she can see Tom’s admiring look. “Well, we’ll just run some tests,” she says, and for once Stella appreciates how efficient she is as she performs spell after spell and narrows down the endless options to something manageable.

“It seems to be a potion,” she says.

“We were doing Draught of Living Death in Potions today,” Stella says timidly. Madam Gilfour nods and hustles Stella out the door.

“Run to Professor Slughorn and tell him he’s needed in the hospital wing.” Stella nods, and starts running down the corridor. “Tell him to bring potion ingredients!” Madam Gilfour called.

 **xiv.**  
Stella cries so much that Madam Gilour doesn’t notice when she casts a standard medical spell on Tom to monitor his condition, gives her a Calming Potion she doesn’t need and tells her kindly but firmly to leave and come back within an hour. While Stella had been gone and Professor Slughorn had taken his sweet time setting up his equipment, Tom reported that he had no feeling up to his knee. Madam Gilfour was looking pale and drawn, and Professor Slughorn was frantically mixing ingredients together.

Stella, once she is out of the hospital wing, runs down to the Potions classroom and uses _alohomora_ on the locked door, rolling her eyes at the lax security. Carefully, she spills the ground snail shells and turtle shells on the desk of some hapless student, who would never have known that they would evaporate into the air, and Tom might breathe them in. Nobody would even think to ask why Tom was the only one who was negatively affected, but even if someone did, she could just say his height and habit of standing throughout the potion-making process probably caused him to breathe in more of the contaminated air.

With that done, she locks herself into a bathroom stall with a small horde of potions ingredients that she’s nicked from the storeroom, and within the hour she’s made an antidote to her own potion, in case it’s necessary. Judging from the people in charge of Tom, she thinks it might be.

“Tom?” she asks timidly as she re-enters the hospital wing. Professor Slughorn and Madam Gilfour turn to her, and wave her towards Tom.

“They’re talking about bringing Dippet in,” Tom says. “They think it was something that happened in Potions, or maybe a negative reaction with the air I breathed in and the food I ate.”

“What have they done to you?” Stella asks, even though she knows.

“Stabilised me. Stopped whatever you put in me. I can’t feel my legs, but it’s been that way for an hour now. They don’t know how to cure me, though. They need the original potion for that.” Stella makes a noncommittal humming noise, and he looks at her. “It’s a pity you probably vanished it at the end of class.”

She smiles at him, pleased that he knows her so well. “You seem safe enough for now,” she says. “Goodnight, Tom.”

 **xv.**  
Tom stays stable throughout the night, and the first thing Stella does in the morning is go visit him. Tom has had an entire night to plot and plan and school his face into a perfect expression. She walks into the hospital room anxiously, looking around for him like she’s scared he won’t be there. He greets her with a little smirk, and she can read his face better than she can read words. _Nice try, darling sister_ , Tom is telling her, _but you don’t stand a chance_.

Stella allows herself a little, triumphant smile as she sits down next to him, only her back facing Madam Gilfour’s office.

“How are you feeling?” she asks.

“Same as before,” he says. “I’ve had all night to think about it. You couldn’t have used anything other than the Draught of Living Death, because that’s what we were doing in class and someone would have noticed if you were brewing something else.” Stella sits back, lets him talk, knows that he will take her casual body language as a challenge. She can see the flash in his eyes as he continues. “The effect of whatever you fed me was like the draught, but slower.” Stella waits for him to say it, knows that he has figured it out. “Turtle shell?”

“And snail shell,” she says, delighted that he only guessed one. His mouth twitches down, so she takes out the bottle of antidote from her sleeve to change the subject.

“An antidote,” she says. “I made it myself.”

“You poisoned me,” Tom said. “At dinner.” When she nods, he laughs, a short thing that sounds like breaking. “Poison,” he says again, smiling at her. “How like a girl.”

“How prejudiced of you,” Stella replies. “Next time I could duel you?”

“Please,” Tom says, settling further into his pillows. “I’d beat you.”

“Don’t be so sure,” Stella says, annoyed at his confidence.

“So what do I do with this?” Tom asks, changing the subject again, twisting the bottle around in his hands. Stella looks at him like he’s crazy.

“Drink it,” she says.

“Shouldn’t I give it to Madam Gilfour to make sure that it’s safe?” he asks her, moving his hand a little so that the bottle catches the sunlight streaming in through the window behind him.

“I don’t trust her,” comes the simple reply. 

“You don’t trust anyone,” Tom says lightly. Without even looking at him Stella can hear the test in his voice.

“I trust you,” she assures him, and passes.

“How touching,” Tom says. “What if you’re trying to kill me again?”

“I wasn’t trying to kill you,” Stella says. “I was never trying to kill you. I don’t know how I’d live without you.”

There’s a pause in the moment, the holding of an all-important breath, and then the world starts again, the breath is released, Tom forgives her. He holds out the potion for her to take the top off, tosses it back, and in less than a minute he is wiggling his toes and pretending it doesn’t matter to him in the least.

“You’d learn,” he says.


	3. iii. the climb {or} it escalates

**xvi.**  
Tom keeps his food away from her after that, careful to only look away when she is looking away as well. He has a newfound respect for her quick, nimble fingers and clever hands, and she can’t deny that she doesn’t appreciate it. He tries to be stealthy about it, but more often than not she turns her head just in time to see him casting soundless spells on his food, trying to ascertain that she hasn’t poisoned him again. She tries to be stealthy about it, but more often than not he sees the thin, sharp smile that decorates her face when she catches him. They laugh together, shoulders bumping casually, carelessly.

She and Tom are unparalleled at the art of pretence; their laughter is always joyful, and sometimes it becomes a competition of who can sound the happiest.

The happiness in the sound of his laughter causes eyes around him to soften, and lips to turn upwards unconsciously. He whispers to her that sometimes, he feels like their false sounds are spells of their own. People around him let their guard down when they hear him laugh.

People around him, yes, but Stella isn’t _people_ , and her brother’s false laughter doesn’t save him from her keen eyes and sharp mind. She notices, quietly, that his gaze is vigilant and quick to return to his food, but she also notices that he forgets to guard his glass of water, positioned on his right-hand side. He doesn’t consider that she might poison his drink, or use a poison that is absorbed through the skin and into the bloodstream, or, as is probably the case, not even use a poison at all if there is a next time. She watches him guard himself fastidiously, carefully, but only against poison in his food, only against the danger that he has already experienced. She is almost insulted at his notion that she would make the mistake of repeating herself, but his constant vigilance is simply too flattering to be insulted by.

She doesn’t think she’s a terrible person. She likes to think that just because Tom seems to be the only person in the world who can understand her emotional capabilities – or rather, her lack of them – it doesn’t make her inherently _bad_. That’s why, she tells herself, she doesn’t act on any of the information she gathers. That’s why she doesn’t slip poison into his drink or rub the sap of scarlet hellebore onto the handle of Tom’s wand or set any other traps for him to fall into.

To be fair, she does try her best to consider all the reasons she has, and a lot of them come down to the fact that it’s not her turn yet, and also that it would be a pity to kill the only person who _understands_. And it’s also true that she doesn’t tell him about any of the weaknesses that she notices – she keeps her observations to herself and keeps her brother vulnerable to an attack, and what does that really say about her?

It’s Tom’s turn now, but he doesn’t make a move against her. She thinks of the one move he’s made against her and misses it, a little bit.

She doesn’t tell him that, though. They pretend to forget that each had killed the other once, and their relationship continues as it always has. 

(For now, she promises herself, watching Tom’s eyes flicker back to his plate and not bothering to suppress the small, satisfied smile that curves around her mouth. For now.)

 **xvii.**  
Neither of them can deny how much they hate the orphanage, and so neither of them bother. 

“Do we _have_ to leave?” Tom asks nobody in particular. She’s sitting on his bed, because she’d been packed and ready last night, and Tom is still finding things under the bed and throwing them in his trunk. Everyone else has left to get to Hogsmeade Station, so Tom sees whatever they’ve left behind as fair game and tosses anything that catches his fancy into his trunk.

Professor Dumbledore’s arrangement from last year to Apparate them back seems to be happening again this year, so they seek him out, and he grasps their hands as he twirls on the spot. The last thing Stella sees before the blackness envelops them is the bitter downwards twist to Tom’s mouth.

The sight of Wool’s Orphanage is enough to make both of their shoulders slump, and Stella straightens a little when she sees the interested look Professor Dumbledore sends them out of the corner of his eyes.

“Let’s go,” she says, grabbing Tom’s hand and heading into the orphanage, because the professor still unnerves her, with his quick eyes and quiet demeanour. He knows far more than he ever lets on, she thinks, even though she can almost see the mocking smile Tom is giving her for being intimidated by something as trivial as a professor. Professor Dumbledore watches them, and he can’t quite hide the sharpness of his gaze in the friendly folds of his face.

“You’re scared of him,” Tom says once they’ve watched him Apparate away, the two of them standing in the doorway waiting for someone to come answer their knocks. The driveway suddenly looks a great deal greyer without a head of auburn hair and an impressive auburn beard to go along with it.

“Yes I am,” Stella says proudly, meeting her brother’s eyes because she knows that’s the only way he’ll take her even a little seriously. “And you should be too,” she adds when he frowns. “Can’t you see the way he looks at us?”

“He’ll never see what he’s looking for, you know. We’re too clever for him.”

Stella shakes her head, and Tom smirks a little at her; she knows that he sees her worries as a weakness, but when she compares it to his casual arrogance she thinks that her worries might be a strength instead.

 **xviii.**  
The first time she meets one of his boys is more of an accident than anything else, but she still figures she’s allowed to be proud that his subtle little recruitments don’t get away from her, because she certainly would have figured it out soon enough.

She’d told Tom to head back to the Common Room without her and sought Professor Slughorn out after class to ask him about what OWL topics she should focus on, and yes, she knew that third year was early to be asking about this but she thought it was important to start thinking about these things early, didn’t he agree? And just as she’d intended, Professor Slughorn had chuckled and settled into his chair more comfortably and gone off into a long spiel which she’d barely paid attention to, and his opinion of her had risen considerably, which had, of course, been the ultimate point of the tiresome exercise.

It’s when she turns the last corner to the Common Room that she sees Tom. He’s leaning down, one hand on this little boy’s shoulder, murmuring something she can’t quite hear. The shorter boy nods eagerly, looking up at him like he hung the moon and lit the sun, and then scampers off around a corner, his eager footsteps bouncing around the corridor for minutes after he himself is out of sight. Stella refuses to listen for the death march in the drumbeat of the echoing footsteps, but the knowledge that it is there is enough.

“Brother mine,” she says, moving forward with careful motions. He turns his head slowly, an equally careful action, and she can’t quite tell whether his calmness is manufactured or whether he knew all along that she was behind the corner and watching him.

“Sister dear,” he replies.

“What was that?” she asks, taking his arm and turning them towards the Common Room. Her mind is setting off fireworks of warning, red alarm flares, desperately trying to get her to take heed of what happened last time she angered her brother. She presses the urgent worry down sternly, her motions never faltering, wondering whether this is the start of a second round, whether she should be scared or excited. Tom shrugs and gives her a little smile.

“Exactly what you thought it was, Star.”

“And what did I think it is?”

“I am consolidating power,” Tom says, returning her gesture and taking her arm. Her body wants her to lean away, to shake him off; her mind welcomes the onset of a game.

“For whom?” Stella asks, trying to keep the test out of her voice. She makes sure to put a little pressure on the hand holding her upper arm, a subtle challenge. His grip tightens a fraction in response.

“For us, of course,” Tom says without any sign of hesitation, and passes. “We are going to rule an _empire_.”

“Are we now.”

“His name is Lestrange, and he belongs to an old family,” Tom tells her.

“What did you do for him?” Stella asks, with every intention to go clean up after her brother.

“Who says I did anything?” Tom asks. When he looks at her it is sideways, a sly slide of his eyes.

“He looked at you like you lit the sun,” Stella says, suspicious of the sly smile that is gracing her brother’s mouth. "You must have done something to earn that look." Tom shrugs, carelessly graceful.

“I took a leaf out of your book, Star,” he says. “All I did was talk.”

 **xix.**  
They keep studying, and Dumbledore keeps watching them, and Stella makes sure that the two of them are so thoroughly ordinary that eventually he stops bothering. The way his eyes follow their movements begins to look a little less aware and a little more like an old habit he can’t quite bring himself to get rid of. The first time that he passes them in the corridor without making sure to keep an eye on them, Tom squeezes her arm so hard that there are probably going to be bruises later, and in return she steps excitedly on his foot to give him matching purple marks.

“He didn’t watch us,” Stella says later, spreading her arms upwards like she might sprout wings and fly away. “He _didn’t watch us_.”

“He trusts us now,” Tom says gleefully. “His eyes slid right over us.”

“We are in a wonderful position,” Stella says dreamily. “This is _wonderful_.”

Tom’s face goes a little pensive, and Stella doesn’t want to admit it but hers probably forms a similar expression.

 **xx.**  
They don’t even dream of wasting this new freedom that they have, and Stella hadn’t even realised how restrained she’d felt when she’d known that someone was watching her. She’d insisted on being as normal and boring as possible, but since neither of them actually had any experience in being normal and boring they’d followed the example set by their housemates. It wasn’t necessarily what they did in their free time – that was mostly unregulated, and most people split their time between the Common Room, the library, and the fields outside the castle, especially in summer – but how they did things. Eating outside of the Great Hall was practically unheard of, routes to and between classes were all pre-established and it took most of the day to finish homework. The two of them had disliked this in particular, and ended up spending hours talking as they carefully pretended to be working. 

They’d both chafed, but thankfully Tom had agreed with her and decided that Dumbledore was watching them, and doing anything out of the ordinary was probably unwise. He’d gone out and talked to more and more people, under the noses of the prefects and the teachers; younger boys who looked up to him like he had done something remarkable in the way that he talked, and, eventually, older boys who pretended to be his equals but were as subservient as the rest.

Tom, who was so naturally contemptuous of everyone else, who held no natural desire to socialise or mingle, became well known in Slytherin House. At first, everyone knew of him. Then everyone knew him, and by the time he felt freedom again he was everyone’s friend.

“Consolidating power. But don’t worry,” he said, every time Stella asked what he was doing. “I took a leaf out of your book. All I did was talk to them.” His words, apparently, held a magic of their own. He hadn’t yet met a person he couldn’t charm, apart from Stella, and perhaps Professor Dumbledore.

“Why do you bother?” Stella had asked him, once. “You don’t need them, any of them. We have power on our own.” Tom had given her a piercing look.

“Social power is just as much a power as anything else, Star. Just because you don’t like making friends doesn’t mean you shouldn’t.”

It was true, and it was her weak spot. She could charm people, she knew that – she was the one who had first developed the idea of words being power, after all, back in the orphanage to equal Tom’s more physical powers – but she could never be bothered to. Making the effort to maintain relationships that she didn’t care about didn’t seem worth it when she could get what she wanted other ways, and she had Tom. It was a little ironic that she had first learned how to weaponise her words and now Tom was the one using it most, she thought, but didn’t say anything.

But when the two of them felt that heady rush of freedom, when bright blue eyes had slid over them absently for the first time, everything changes.

They don’t pretend to take a million years to study anymore, and suddenly they have a million years of free time: they promise each other to study higher-level curriculum, to learn Apparition, but their first point of call is to explore the castle as thoroughly as possible, committing every square inch of the place to memory.

“I will never forgive the professor for stopping us from doing this,” Tom says once as he studiously turns at only left corners, to see whether it will lead them in a circle. “We could have done this years ago, Star. _Years_.”

“Practice,” he says another time, when they have finished with the fifth floor and climbed up onto the sixth to find a row of portraits. “You can charm them, can’t you?”

“Of course I can,” Stella says on a sigh, stepping away from her brother and starting to talk. It only takes a few days for the portraits to willingly yield up the secrets of the castle they knew to “such a lovely, clever, interested girl,” as one portrait had put it, waving his goblet of wine around merrily and staining his sleeping friend red.

“I found the most amazing place,” Tom says, the day after she has discovered what the portraits call the Room of Requirement. His eyes are shrewd as he looks at her, and she looks up at him as innocently as she can.

“Really?”

“Yes,” he says. His gaze does not let up. “The portraits call it the Room of Requirement.”

“It sounds wonderful,” Stella says, as innocently as she can. She knows without a doubt that it would fool anyone else, but Tom’s sharp gaze does not let up in the slightest. “You’ll have to show me it tomorrow.”

He swings around to sit next to her. “When were you going to tell me?”

“You would have found out in any case,” Stella says. “But if you hadn’t, I would have showed you.”

“The pot’s calling the kettle black, anyway,” Tom says thoughtfully. “But you know that, don’t you? You found out about the third-floor corridor to Honeydukes.”

“I was wondering if you’d tell me,” Stella says.

“Well, you broke character for me,” Tom returns, almost teasingly. “It was only fair.”

 **xxi.**  
Slowly, over time, Tom has amassed quite the little following. Stella prides herself on not letting it get away from her; she catches the looks of surprise that some of the students exchange when they see Tom surrounded by a motley group of six boys, but she remembers each and every one of them.

What scares her, more than the fact that Tom has amassed his power so easily, is that she doesn’t know why he’s doing it, or what he’s using to keep his little band together. As far as she can tell they don’t have a cause, but a common cause would be one of the only things that could keep such a motley group of mismatched boys together.

“Stella,” Tom says after he’s sent his boys away with a wave of his hand; they scamper, obediently, and Stella watches them huddle in another corner, talking animatedly. “Don’t you ever wish we knew more about our family?”

She can’t help thinking that this is a turning point.

“No,” she answers honestly, and gives him a smile. “I have all the family I need.” He rolls his eyes, but she can see the faint smile hovering over his face.

“You never wonder? Where we came from, why we’re – like this?”

“Like what?” Stella asks innocently. Tom grabs her wrist and pulls her outside the common room. “Now where are we going?”

“You know as well as I do that we’re different, _Star_ ,” Tom says, a pointed reminder of what happened just after the nickname was coined. She makes sure to keep her face still and inscrutable.

“Are we taking a philosophy class now? Are we pondering our own existence?”

“You never wonder where we came from?” Tom pushes. “Our origins, our roots?”

“No,” Stella says. “I don’t care. I couldn’t care less about our origins and our roots.”

Tom drops her wrist and runs a hand through his hair. “Why not?”

“Why would I? My _origins_ don’t define me. Why are you asking, why do you care, all of a sudden?”

“Oh, nothing,” Tom says vaguely. “Just a couple things that the boys were saying.” Stella shoots him a sharp glance, but he meets it with his own hard glare, and their conversation falls back into silence as the two of them make their way back to the Common Room.

 **xxii.**  
Things truly start to change in their fifth year. Both of them are aware that this is a stereotype, that the oncoming OWL exams usually cause students to have deep and life-changing epiphanies, or something equally ridiculous.

“The only thing worse than fifth year would have been seventh year,” Tom says when it is over, and Stella shrugs.

“I don’t know. I think most people stop caring by seventh year,” she says, and Tom nods pensively.

Still, neither of them can help that the chain of events unfolds as it does. It isn’t their fault that they had happened to read the letter that the owl had delivered – well, technically that one is their fault. The two of them check most of the correspondence that comes through the owls in the early hours of the dawn when the owls have arrived with their letters but breakfast hasn’t started yet, because it’s an easy way to stay informed. And when they’d seen a letter addressed to a _professor_ – well. Even with the risk of a professor seeing through their resealing spell, correspondence from someone outside the school to a professor through the owl post system was such a rare and precious opportunity that there was no way they weren’t taking it.

And once they’d read the letter, there was no way that they were going to simply stay inside that night. They’d settled inside a bush and cast Disillusionment Charms on each other and waited in their convenient little hiding spot before the arranged meeting.

It _certainly_ wasn’t their fault that Professor Kettleburn’s black-market friend was so desperate to get rid of his commerce that he forget business sense entirely, and named a price so cheap that really, neither Tom nor Stella blamed the professor for being convinced it was a fake and throwing it out on the compost heap he kept in the backyard, purportedly for educational purposes but actually because he was the laziest professor in the school.

It’s most certainly neither of their faults that they are more pragmatic that Professor Kettleburn, and gleefully decide to grab the egg off the pile and sneak back up to the castle with it, exchanging increasingly unlikely cover stories they can use if a particularly enterprising Prefect finds them.

“Maybe we were walking in the Forbidden Forest and found it.”

“Maybe we tripped over it on the grounds.”

“Maybe we’ve just taken it to the professor to find out what it is and he just told us it was a big, fake egg.”

“They’d probably believe that,” Tom says after a moment of quiet. “The stupid sods would probably believe that story. Did you ever hear of anything so sad?”

 **xxiii.**  
Stella is the one to find the hidden passageway in the girls’ bathroom. It’s not really that much of a triumph, because she and Tom are researching Parseltongue and the two of them are both spitting random words out at one another. It _seems_ to be flowing naturally, and Stella can understand what he’s saying, but she’s not certain whether she only understands it because of the book or because she can speak it, and whether this hissing and random spitting will let them communicate with their Basilisk in the still-hypothetical situation that it hatches.

“Quiet,” Tom says as the door rattles slightly. The person outside gives up, but they can hear exasperated grumbling from outside about the door malfunctioning _again_.

“I hope you can open that later,” Stella says, nodding at the door and barely aware that she’s hissing rather than speaking, and Tom has opened his mouth to reply when he's interrupted by the grinding noise of a tunnel opening from one of the sinks.

They don’t even have to think about it before they find themselves sliding down the dark hole.

“How are we going to get back up?” Stella wonders when they land, peering up at the already-dim light that appears now only as a tiny pinprick. Tom shrugs.

“We’ll find a way,” he says, unconcerned. They move further into the room, holding their lit wands aloft, and lacing their free hands together so tightly that Stella can feel her heartbeat in her fingers.

“I can’t believe nobody noticed this,” Stella says. “I mean, don’t they have floor plans or something?” Tom shrugs at her.

“You know nobody sees anything.” Her mouth twists downwards at his words, but she doesn’t rebuke him. He smiles at her, understanding on his face. “I know,” he says, and he expresses everything in those simple words.

They find torches and light them, trying to cheer the place a little and failing. They can see the bones of an old Basilisk, taller even than the two of them put together. Stella levitates Tom up to the bathroom and he runs to fetch a broom from the Quidditch stores as she tries levitating herself, just to see whether it will work. She has yet to reach a decision on the matter when Tom comes flying down with the Basilisk egg. She places it on the floor and tells it to open, that the world is waiting for it, that it will have a long and gloried future, nonsense to try and get the thing to come out of the egg, if there’s anything there.

 **xxiv.**  
Stella is the one who takes Care of Magical Creatures, and so Tom graciously gives her the task of trying to identify whether the egg is real. As it turns out, however, it’s very difficult to tell the difference between a Basilisk egg and even a half-decent fake. The books she can dig up in the library on the subject all tell her that this is meant to be a camouflage mechanism, and specify helpfully that it probably developed ‘at the dawn of time’.

“As far as I can tell it’s real,” she says, dropping the books on his bed. “But then, according to most of these, half the fakes in the world are indistinguishable from the real eggs.”

“So we just keep talking to it, I guess,” Tom says.

“That’s something else,” Stella says. “These say that Basilisk eggs are chicken eggs, hatched underneath a toad. We –”

“Do not have a toad,” Tom says.

“Exactly.”

“I’ll get us a toad from somewhere,” Tom says carelessly.

“Next Hogsmeade trip we can Apparate to Diagon and buy one,” Stella proposes. Tom considers this and nods.

The egg, as it turns out, is not a fake. It cracks first, and Tom and Stella jump back and look away, Tom hissing out instructions for the basilisk to close its eyes. There is a nasty series of noises as the baby Basilisk presumably eats its toad incubator before it replies that its eyes are closed, and then neither of them can resist looking at it, inspecting it, reaching out to touch it.

“You’re beautiful,” Stella tells it.

“So beautiful,” Tom agrees, and the basilisk arches happily underneath their touch.

Stella looks up at her brother over the body of their basilisk, and he smiles at her, something wildly excited in his eyes.


	4. iv. the pause {or} a crack forms

**xxv.**  
In hindsight, Stella thinks that maybe this is when it starts. But that might be too easy – with the benefit of hindsight it is always easy enough to think of particular moments, pinpoint them as the start, or the change, or something great and pivotal. This wasn’t a simple moment that changed everything but a catalyst which started something gradual. The basilisk was what gave Tom his first taste of power.

“Three people are in the hospital wing,” Stella says, carefully nonchalant. “Petrified, for some reason.”

“Is that so?” Tom asked in reply, just as carefully careless.

“Yes,” Stella says. “And I’ve been thinking, and do you know, the only thing I can think of with the ability to do that –”

Tom sits up sharply, and makes a shushing noise. “I know,” he says, looking around to make sure that nobody could hear them.

“So it was her?”

“Yes,” Tom says, and appears to brace himself for the question he knows she’s going to ask next.

“Why?” He shrugs, and Stella can barely believe the slump of his shoulders or the defeat in the action. “Tom?” she asks, and her voice is a lot more tentative than she gave it permission to be, because this behaviour is unexpected, and frankly that scares her.

“I don’t know –”

“Lie,” Stella says, folding her arms, because Tom might have fooled anybody with that tone but he could never lie to her.

“Alright! I like it,” he says, fists clenched, looking up at her defensively. “It’s power, Star. This is real power. It – you need to try it, you’ll see. It’s the most amazing feeling –”

“What for?”

“What?”

“Why are you sending her out after people? Just power for power’s sake?”

“And what’s wrong with that?”

Everything, Stella wants to say. “Power for power’s sake makes you nothing better than mad,” she says instead.

“Let me be mad, then,” Tom says. “If this is madness – it’s wonderful. I never want it to stop.”

 **xxvi.**  
Stella shrugs and tells herself that it’s not her problem, that if Tom wants to go around Petrifying people then it’s really just his problem, but she can’t ignore the fact that basilisks can kill with a glance. Really, it’s only been luck that everyone the basilisk’s come into contact with has only been petrified, and not turned into stone.

She wants to ask a professor whether there’s any cue for being turned into stone, but nobody can see anything and she’s pretty sure that nobody’s even thought of a basilisk being behind the petrified students – not even Professor Kettleburn, to whom it should be damned obvious.

“He probably doesn’t even remember,” Tom says scathingly when she mentions this to him. “How can he possibly be expected to remember something that happened months ago?”

“That’s just asking too much,” Stella agrees, faux-sympathetically, and Tom snorts.

The books in the library are perhaps even less enlightening than not asking the professors: they tell her that there is no cure, there is only one cure which requires the full moon and a werewolf, there are six cures because of the six types of dragons, or there is one cure which has to be performed once on each hill around Rome. One book even goes so far as to state the basilisks only petrify, and that being turned to stone is only a myth. Stella starts experimenting, fooling around with the draught of life, asking the newly-christened Anguisa to turn things to stone and then attempting to de-stone them.

“No success?” Tom asks, hopping off his broomstick and surveying the stone animals scattered around the room.

“No,” Stella says, not surprised that he’s found out what she’s doing.

“I hope none of these are pets.”

“Really, Tom,” Stella says, rolling her eyes as she turns to face him. “I’m not that sloppy.”

“Glad to hear it,” he says. “Why are you doing this, exactly?”

“Just in case,” Stella tells him.

“You’re such a worrier,” Tom says fondly, patting her shoulder. “Anguisa would never hurt us.”

“Never,” Anguisa agrees. 

**xxvii.**  
Then – well, and then. Stella doesn’t particularly like to think about the next and then, although she knows that it holds a peculiar sort of delight for Tom.

And then, a girl is found in the bathrooms, turned to stone with the tears still visible on her face.

“Why was she crying, do you think?” Tom asks once they’re back down in their chamber of secrets, as they’ve started to call it, his arm around Stella, who is doing an excellent job of not looking repulsed by all this. “Do you think she knew, in her final moments? What was coming for her? Do you think she was crying from fear?”

“Her name was Myrtle Warren,” Stella says softly. She isn’t quite sure how she feels about this; she knows that she’s not sad at the girl’s death, or angry at Tom about it, but she does know that this was a death for no good reason, that Tom killed someone just because he had the power to and he _could_. She knows that this death lacked logic and that angers her. “She was consistently bullied by another girl named Olive Hornby.”

“Is that so,” Tom asks, sounding distinctly less pleased. “Of course you paid close enough attention to everybody to know that. Next time just let me have my moment, Star.”

“Next time? Is there going to be a next time?” Stella asks him. He shrugs, her beautiful careless brother.

“Why? Are you against it, sister dear?”

“Yes,” she tells him, because he knows exactly when she’s lying to him and so there’s really no point. “At a fundamental level, this lacks logic. There’s no good reason for killing her.”

“Isn’t there?” Tom asks. “Isn’t the fact that I _can_ , and I want to – isn’t that enough for you?”

Stella shakes her head, the stone body of Myrtle Warren still clear in her mind.

 **xxviii.**  
“It needs to stop,” Stella says the next day, when she meets Tom in their chamber of secrets.

“What needs to stop?” Tom asks, all fake-innocent.

“Anguisa,” Stella says. “And not just because I don’t like it. There’s talk of getting Aurors in to patrol the place, Tom. Everybody’s scared.” 

“Good,” Tom says.

“Not good,” Stella returns. “You know that.”

“Do I?” Tom asks. “Don’t you just want me to?”

“Both,” Stella tells him. “You need to stop this, or I will.” Tom looks at her consideringly, but both of them know that neither of them want a fight.

“How do you propose we stop, then?”

“I found a stasis spell,” Stella says, taking the parchment she’d written the spell down on. “We can put Anguisa to sleep, and put parameters on the sleep.”

“Like, she could only be woken by Parseltongue?”

“Yes,” Stella says. “That would work.” There’s a long silence where the only noise is the constant damp dripping of water that seems to permeate the room. “You have all the power you need on your own, Tom,” Stella says softly, knowing that this is the argument most likely to sway her brother. “She’s an excellent tool, but you don’t need Anguisa.”

Tom sighs, and the noise echoes around the room wetly. “You always know exactly what to say, Star,” he says. “Alright. We can do the spell together?”

“Yes,” Stella says, and they tuck Anguisa into the open mouth of Salazar Slytherin’s likeness, murmuring words of comfort to her, that she’d be okay, that they’d wake her, they’d come for her, that she was safe here, nobody but a friend could find her, and as Stella performed the spell Tom swept his protective magic over her, until Anguisa is fast asleep, taking deep, gentle breaths.

 **xxiv.**  
“We need to clean up,” Tom says.

“We need to do no such thing,” Stella says, although really, yes they did.

“Yes we do, and you know it,” Tom says. “People are still scared. We need to tie this up, neatly, no loose ends.”

“You wouldn’t even dream of giving them Anguisa,” Stella says, and Tom shakes his head at the thought.

“No. And we wouldn’t have a good explanation for finding her, either. It needs to be something else.”

“Or someone else,” Stella says thoughtfully. Tom nods, encouraging her to continue, so she does. “We’d have to pick someone who’s already known for their affinity to rule-breaking and dangerous creatures –”

“The half-giant,” Tom interrupts, and Stella turns to look at him, a slow smile curling over her mouth at the perfection of this plan.

“Rubeus Hagrid? Yes, he’s be the perfect foil. Half-giant,” she says thoughtfully. “There are all sorts of wonderful terrible rumours that go around about giants. Third year might be a little young, though –”

“Not too young,” Tom says. “And he set himself up for this so perfectly. You know what he has under his bed?”

“You have been doing some research,” Stella says, not that surprised. “No, I don’t know. What does he keep under his bed?”

“An _acromantula_ ,” Tom says, his eyes dancing, and Stella can’t help but laugh out loud at this.

“No!”

“Yes!” Tom says, his laughter joining hers. “And there are all _sorts_ of wonderful terrible rumours that go around about Acromantulas as well, aren’t there?”

“Oh, absolutely,” Stella says. “You picked the perfect fall guy.”

“Don’t I know it,” Tom says nonchalantly, but she can tell that he’s preening. “So how are we doing this?”

“You can discover him,” she says. “You’re a prefect, aren’t you? And he really can’t be that discreet about his little secret. It’ll be easy enough for you to drag him in by the ear.”

“Professor Dumbledore, though,” Tom says, looking at her. “I’d be surprised if he didn’t know about it. You were right about him,” he admits, “now that I’m looking for it – he’s very observant.”

“Well, go to Dippet. You’re right about Dumbledore,” Stella says, frowning a little as she worries at the edge of her quill. “But if you go straight to Dippet, get him properly convinced –”

“And most of the other teachers’ll probably see sense,” Tom says musingly, tapping Stella’s quill away from her fingers.

“They don’t see much,” Stella agrees. “If you can convince Dippet you can probably convince them.”

Tom’s mouth twists upwards, his smile slick around the edges. “Of course I can convince Dippet,” he says. “Who do you take me for?”

“The squeaky-clean Head-Boy-in-waiting that you are,” Stella says perfectly seriously. Tom rolls his eyes at her and checks his watch.

“I should get ready for patrols,” he says.

“You have one tonight?” Stella asks, and when Tom nods her slow smile returns. “My, you did time this conversation well,” she says teasingly, and he grins at her, pulls her forward for an unexpected hug that she returns without the slightest sign of hesitation.

 **xxv.**  
While Tom is out on patrol, Stella shadows him, carefully making sure that he doesn’t know she’s there. He talks amiably enough with his patrol partner, and peers down at the dungeons.

“Ugh, do we have to?” his partner grumbles, but follows him down, and Stella can hear a couple of muffled cries of surprise coming from the corridor.

“Rubeus Hagrid?” she hears Tom ask, in a perfect tone of surprise.

“What – what’re you two doin’ down here?” Hagrid asks, sounding a little terrified, as well he should be.

“Is that –” the patrol partner starts, sounding horrified.

“An acromantula, Hagrid? Really?” Tom asks. “So that’s what’s been causing all the attacks around the school,” he says scornfully, over the loud protests of the third-year student and the equally loud gasp of realisation that comes from the patrol partner, who is taking a rapid nosedive in Stella’s regard for him.

“Aragog’d never!” Hagrid cries passionately. “It wasn’ him!”

“Stand aside, please, Hagrid. I don’t want to do this by force,” Tom says, and Stella is impressed at the perfect mix of sadness and reluctance and slow-burning anger in his tone.

“He never killed no one!” Hagrid tries again. From the sound of it, he’s backing up against the door, and Stella can hear an odd clicking and rustling growing louder.

“Come on,” says the patrol partner, “Tom, let’s go, let’s go –”

“Alright,” Tom says, and the two of them make their way up the stairs. Stella presses herself carefully into a corner, and Tom turns his patrol partner around and says gently. “If you want, I can go talk to Dippet.”

“Oh, thank you,” the patrol partner says. “He scares me, and I’d have no idea how to break the news, and –”

“It’s not a problem,” Tom says graciously, as Stella is growing more and more impatient for them to carry on. “But if he asks, I will be saying you were with me.”

“That’s reasonable,” the patrol partner says, and hightails it out of there without another word. Stella hears Tom’s footsteps retreat towards the headmaster’s office, and spares a moment to hope that he can put on a believable act for Dippet and, more importantly, Dumbledore.

When she’s sure that Tom isn’t coming back, she casts a Disillusionment spell on herself and runs down the dungeon stairs lightly. Rubeus Hagrid, at least, is not too intolerably foolish; he’s long gone, and the closet door is open. Carefully, Stella steps into the closet and inspects it for spells. There are several basic Concealment charms through the closet, and carefully she undoes them all – they’re shoddy things, easy to undo and certainly easy enough for the Auror department to see through, but she doesn’t want to take any chances. Then, carefully, she goes about gathering all the signs that an acromantula was there – which, again, Rubeus Hagrid isn’t too unbearably foolish, he’s been cleaning up after his pet. Stella gathers together everything she can find, pieces of skin, hair, even a few lost claws – and makes them all larger, clear and obvious and undeniable, and spreads them around the closet again, exactly where she found them. By the time she’s finished with it, there is no conclusion anybody with half a brain could reach aside from ‘someone was keeping an acromantula in this closet’.

Satisfied, and a little annoyed that Tom didn’t think to at least have some proof with him – her lovely, arrogant, careless brother – she goes back to the Common Room and sits on Tom’s bed to wait for him to come home, as she knows he would want her to. The next thing she knows, he’s come back from his patrols very late, his eyes dancing with barely-concealed delight and a repressed smile that Stella can see as clearly as if he was wearing it, and the excitement coiled in his muscles tells Stella everything that she needs to know.

“It went well, I presume?” she asks, moving over on the mattress. He sits next to her and nods.

“Oh, you should have seen me, Star, I was wonderful,” he says. “Schoolboy-shy and _so_ altruistic, you wouldn’t have believed it if you’d been there.”

“I think I’d have found a way,” she says, sitting up next to him. “Tell me,” she says, and this is clearly the invitation he’s been waiting for.

“I ‘found’ Hagrid,” Tom says, and Stella can hear the quotation marks around _found_ , “like we agreed, and then I backed off and went to the Headmaster, and told him – oh, so much twaddle I’m surprised I could say it all with a straight face, Star. Stuff like, I’d caught the person responsible for the attacks, but he – oh no, _they_ , they were young and irresponsible and I didn’t want them to be punished too harshly because they hadn’t really known what they were doing, you know –”

“How long did you blather on in that fashion?” Stella asks, almost helplessly amused by the mental image, but there is pride underneath the amusement; apparently her brother has learnt subtlety, then, and while she isn’t going to take credit for it in front of him she will most certainly take credit for it with just herself as a witness. Tom shrugs.

“A while. And Dippet – he swallowed it like a _baby_ , pushed my very gently and said it was important for the world to know so Hogwarts could be safe and I needed to understand that the Ministry would do what it deemed best, you know, all that – it was like a dance, you know, and he thought he was leading but –”

“But you were leading him,” Stella says, the smile on her face intact.

“Anyway, I came out with Hagrid’s name,” Tom says, winding down a little, the restlessness under his skin growing a little less pronounced as he starts to finish talking it out. “And Dippet sent me away, and I’m pretty sure that he’s calling a teacher’s meeting right now.”

“Excellent,” Stella says. “And where is Hagrid now?” It’s a test question, but she’s careful not to ask it like one.

Tom shrugs, careless. “Probably sleeping, or maybe he’s been smart and let his friend go. Dippet has a pensieve, I can offer to use that as proof if we really need to.” He turns to her, and even in the darkness of the dormitory she can see the smile of realisation that hooks his mouth upwards. “Oh, but that won’t be necessary, will it?”

“Not a bit,” Stella says. “Our friend Rubeus Hagrid isn’t intolerably foolish –”

“Foolish enough to keep an acromantula pet,” Tom says, amused. “But go on.”

“ _Thank_ you. He had a lot of Concealment charms on the closet, to hide the claw marks,” Stella says. “And he’s been cleaning up most of the skin and shed hair.”

“But?”

“But of course he didn’t get it all,” Stella says. “I just made everything – a little more obvious, is all.”

“So that it’s unmistakeable.”

“So that it’s unmistakeable,” Stella repeats, and Tom pulls her in for another rare hug.

“We make the perfect criminals, Star,” he says happily, and she smiles and hugs him back.

 **xxvi.**  
Rubeus Hagrid is all anyone can talk about during the next few days; he’s been caught with an _acromantula_ , would you believe, and he’s been summoned to a Ministry hearing, and his wand’s been snapped, and he’s been expelled!

“Goodness me,” Stella says, when the Headmaster Dippet presents Tom with a heavy, pretentious statue for Services to the School. “You have the Head Boy position in the bag, I’d say.”

“I hate this,” Tom says, glaring at the statue. “Services to the school? I wasn’t _serving the school_. I’m nobody’s damn servant.”

“Here, I’ll get rid of it,” Stella says. Tom gives her a sceptical look, and she laughs. “I won’t destroy it or anything, silly, I’ll just stick it in the trophy room, where you won’t ever have to look at it again, and students in detention will have to polish it.”

“Now that thought, I don’t mind,” Tom says, relinquishing the statue to her.

When she comes back statue-less, she also has bad news.

“So,” she says. “I have bad news.”

“Oh?” Tom says, raising an eyebrow at her. “Not to do with our perfect crime?”

“A little,” Stella says, and Tom sits up, gives her his full attention.

“What is it?”

“Dumbledore,” Stella says, and Tom’s mouth twists downwards. “He – well, he convinced Dippet to keep Hagrid at the school, and train him as groundskeeper.” Tom stares at her, for a moment, his mouth a little open in true surprise. To be honest, she’d had a similar reaction when she’d overheard the news.

“Damn,” Tom says eventually. “But – there’s no way he can prove his innocence, is there?”

“We didn’t forget anything, if that’s what you mean,” Stella says. “It was the perfect crime. But I think there is something we didn’t foresee needing to consider,” she says, and at Tom’s impatient gesture she rolls her eyes and goes on. “Acromantulas take a few years to develop their oratory skills, but they remember everything that happened to them.”

Tom bites his lip. “It’s okay,” he says eventually. “They don’t naturally like humans, the thing wouldn’t come forward to clear Hagrid. But that’s just – inconvenient,” he says, running his hands through his hair in an agitated gesture which speaks of more than just plain inconvenience. “Damn it, Dumbledore.”

“We’ll figure something out, anyway,” Stella says. “We can go acromantula hunting if we feel like it’s going to become a big thing, but to be honest I don’t see Hagrid pushing.”

“That’s true,” Tom agrees. “He knows Dumbledore is his only backer.”

“And he should know that if he pushes too hard it’ll be easy enough for him to lose his job,” Stella says. Tom meets her eyes, and they nod.

“Not quite perfect, but pretty close,” Tom says. His satisfied smile makes a reappearance, and Stella returns it readily.


	5. v. the acceleration {or} cold resolve

**xxvii.**  
“Do you know what we need?” Tom asks one day, coming up from behind her in the library in a semi-obvious attempt to make her jump. Because of this, she carefully doesn’t react to his words or his presence other than to straighten lazily and put down her quill.

“No, I don’t,” she says. “Tell me, what do we need?”

“A project,” Tom says, “and I have the perfect one.”

“You’re so full of ideas lately,” Stella says. “Better be careful or one day you might burst with them all.”

“Ha ha,” Tom says, but he’s giving her a carefully assessing look, to see whether it was a threat; she gives him a reassuring smile to indicate that it wasn’t, and he sits back, seemingly at ease again. “We need to get this Trace off us.”

“The Trace?” Stella asks, and frowns. “It’s annoying that we can’t do magic in the summers, I’ll admit, but what would we do even if we could? Home renovations?”

“Oh, someone’s feeling funny today,” Tom says, rolling his eyes. “Isn’t it enough that we want to do it? And it’ll be useful to know later,” he adds, when he sees that she’s isn’t very impressed with this ‘because i want to’ reason again. “To get around Ministry-laid magic.”

“Alright,” Stella says, because she’s bored with the constant revision everyone seems to expect her to do, because they don’t understand that she knows all this already. This is a harmless enough project, she thinks, and perhaps it will help get that power-hungry gleam out of Tom’s eyes, the one he’s had since Anguisa and Myrtle Warren and Rubeus Hagrid, the one that makes an appearance every time he talks to his gang of boys. “I’ll go find some books on the subject,” she says, standing.

“Excellent,” Tom says, hooking his arm in hers and pulling her forward a little too forcefully. She sidesteps the table and chairs between them easily, and passes his small test of her grace. “I’ll come with you.”

While she’s searching for books, she finds Tom sitting at a pile of newspapers, reading over them intently, with a sort of raw hunger in his face that Stella has gone a long time without seeing.

“What, do you think the secret of the Ministry is going to lie in a Hogwarts newspaper?” she asks, and he actually _jumps_. Her shoulders immediately stiffen, her eyes wide at this breach of their etiquette, their unspoken language of grace and poise that never slips. He scowls straightaway, turns around and gets up with all the grace he can muster to compensate.

“Let’s go,” he says, trying to grab her arm, but she evades him and sits in front of the newspaper that he’d been poring over so intently.

“What are you looking for?” she asks softly, running her fingertips over the page. And because Tom can’t deny her the answer to the question, he sits down next to her, leaning on her so that she’s carrying more of his weight than he is.

“Wizards named Tom Riddle,” he confesses, and when Stella stiffens so does he. “I know – Star, I know. But I wanted to find out. Where we came from – our blood, our roots, our origins.”

“Have you found anything?” Stella asks, forcing her body to go loose and relaxed again, and Tom shakes his head, his disappointment so evident in the way his body slumps against hers again. “Why assume that the parent was Tom Riddle? Why not Merope Gaunt? That was her name, right?” Stella feels like she should remember her own mother’s name with a little more care, when Mrs Cole had sat them down so very gently and told them that their mother’s name was Merope Gaunt and that she’d left them and that’s why they lived where they did and had no parents. The two of them had taken the speech rather too well, she remembers; Mrs Cole had given them an assessing look and sighed something about them being twins making things different.

Tom shrugs. “Why’d she leave us if she was a witch?” he asks. “Why’d she leave us at a Muggle orphanage if she was a witch? At the least she should have left us in a magical orphanage.”

“And are you not going to try and find her?” Stella asks, and when Tom shakes his head she frowns and asks, “Why?”

“Because, Muggle or not, I might kill her for leaving us,” Tom says, and Stella laughs.

“Oh, I’d join you,” she says. “And what are you planning to do with Tom Riddle our father, since you’re searching so desperately for him?” Tom goes through a series of emotions at this – he rankles at the label of desperate, but then he smiles; still startled, at first, and then all teeth.

“I just wanted to see what kind of magic we came from,” he says, “but I wouldn’t mind – well, _reprimanding_ him. After all, he left us as much as mother did.”

“I’ll join you in that,” Stella promises, thinking about a misspent childhood in the thin walls of an orphanage; of never quite having enough to eat, never quite being warm enough. Of only having one person in the whole world to understand her.

 **xxviii.**  
“Well, if we’re planning to, ah, reprimand Tom Riddle our father,” Tom says, “we still need to get this Trace taken off us. Unless you want to wait another two years.” That’s how they talk about them now, their parents – always name first, to disrespect them, and then ‘our father’ or ‘our mother’ instead of the simpler addresses alone, to distance themselves from the people who were of their blood and abandoned them. Merope-Gaunt-our-mother and Tom-Riddle-our-father have become second nature labels for people that they’re hunting.

“Not a chance,” Stella says laughingly, and that is how they spend the entire year they should be preparing for OWL exams in the library instead, poring over books which have absolutely nothing to do with anything that they’re going to be tested on. Neither of them bother to bring it up, though, because they really don’t need to revise, and if pushed they’d probably admit that they didn’t understand why other people needed to revise: once they had information, it stayed with them.

The books that they read are far more fascinating than exam preparation, anyway; about the Ministry and its old, old magic; about instinctual magic, and magic that can be performed without a wand; about the most _fundamental_ parts of magic. They research the habits and complex spells that the Ministry has used since the its induction, those spells which are so deep-rooted that nobody knows them, any longer, just depends on them.

“These are dangerous,” Stella says, carefully studying one of the many layers of spells which keep the Ministry stable and secure in its precarious underground environment, one that she can’t imagine anybody remembers and everybody simply takes for granted. “Imagine if we took one. It would cripple them, it would –”

“It would be glorious,” Tom says, and laughs at the look she sends him. “Oh, don’t worry, Star. I’ll be good, I won’t do anything. Not without your approval.”

“I think what you mean is _not yet_ ,” Stella says, not fooled in the slightest, and Tom laughs. Her dear brother has been growing more power-hungry, and she can’t quite ignore it; ever since Anguisa, ever since he killed someone and she helped him frame someone else for it. She remembers what she’d said to him, what seems like forever ago - _power for power’s sake makes you nothing better than mad_ – and wonders whether her brother is going mad, wonders whether she can stop it.

“Maybe,” he says. “I don’t know yet. Let’s keep going.”

They find the closest approximation to a Trace in the textbooks, and struggle with it, experimenting; the last thing they want to do is injure themselves, after all.

“It’s not a wand thing,” Stella says, “because this extends to magic that happens around you, as well. So we don’t have to deal with wands, I suppose.”

“Well, wonderful,” Tom says. “We don’t have to deal with wands. That’s one thing in a million that we’ve eliminated.” 

“Unless they put the Trace on wands?” Stella asks nobody in particular, and Tom groans loudly and buries his face in his hands.

“You’re the worst,” he tells her, but pulls the book that she’s reading closer to him anyway.

Stella hasn’t thought about her parents since that one talk they’d had, and she hadn’t cared about her blood or her roots or her origin for a long time, if she ever had. But this – suddenly, she has a purpose. These people had left her in an orphanage which was obviously rundown and overcrowded, a place with no enough food and walls that were too thin, with a hurried matron and other kids who were just so unbearably _stupid_ , who never understood anything.

She thinks that maybe this is what Tom feels like, all the time; all this hard cold resolve, like steel, roiling around inside her, that he just needs to point into something, a project or an action or perhaps a person. She’s going to kill her parents, and it will be for revenge but also because they’re shitty people, and she thinks that she might enjoy this very much.

The first time they say it to one another it feels like it should be more momentous.

“We’re going to kill our mother Merope Gaunt and our father Tom Riddle,” Stella says softly to him, in the Common Room, just to see what the words will taste like, what they feel like when they curl over her tongue. And Tom knows her so well that all he does is turn to her, an amused expression on his face.

“And what do that words taste like, Star?”

She grins at him, making sure that her smile is all teeth, just like his most savage ones. After plenty of inspection in bathroom mirrors, she’s concluded that savage smiles never look as if they belong on her much gentler face, and that the juxtaposition is always jarring. She saves up her most savage smiles for special occasions, and this is certainly one of those. “They taste like revenge and resolve,” she tells him, and he smiles back, a genuine centre hidden in its coldness so thoroughly that she is the only one who would ever have a hope of picking it out.

“Good,” he says. “Because we’re going to kill our mother Merope Gaunt and our father Tom Riddle.”

“And how do the words weigh on you when you say it?” Stella asks her brother, because she knows that’s how he measures his words. His smile at her this time is all teeth.

“They sound like something perfect,” he says, and neither of them can help the identical satisfied smiles that stretch across their faces.

 **xxix.**  
Research, then, is mostly focused on the Trace and losing it, but it is Professor Slughorn, of all people, who ends up giving them what is possibly the best tool of all when it comes to this crime they are planning, who makes it possible. Well, not entirely possible. Stella has no doubt that she and Tom would have pulled it off in any case, with or without what he gives them, but she has to admit that this makes it a million times easier: 

“Will you ever not like sugared pineapples?” one of the boys around them asks, his tone more joking than serious – Lestrange, Stella remembers, one of Tom’s cronies, a boy who looks at Tom like her brother has all the answers in the world. Maybe he does. Slughorn just laughs in response to the question, patting his overly-large stomach as he winks at Tom and sets the gift aside as Tom pastes a smile on his face, the expected response to a wink.

“Never,” he declares. “The only way that’ll happen is if someone messes with my memories.”

“Is that possible, sir?” Stella asks, interest piqued. Tom sends an amused look her way, probably expecting her to get laughed at and shot down. Half the boys in the group follow his lead and give her derisive stares, and she wants to laugh so badly that she needs to duck her head and bite her lip to keep from making a noise. She lets them think they’ve shamed her through her passiveness, and through the corner of her eyes she can see Tom repressing a smile of his own. Instead of shooting her down, however, Slughorn heaves himself upwards and settles himself more comfortably in his chair.

“Oh, yes,” he says. “It’s just something else you can do with the memories that you put in a pensieve. I’ve never had much reason to know about it, though, my dear,” he says, tipping her a wink that she barely registers, and smiles at completely out of habit.

Tom is the one who has captured her attention; Tom, who has done nothing so out of the ordinary that the boys around him have noticed it, but to Stella his excitement is palpable, shows itself to her in the way that his back stiffens and the corners of his smile suddenly become so much more stiff than they were before. 

“We need to learn this,” he says, pacing around his bed while she sits on it.

“It would be so useful, this could – forget manipulating people,” Stella says, “with the right memories we could make them do anything.”

“And not even resort to Unforgivables,” Tom says, before tilting his head to one side. “Maybe we could lift the Ministry taboo on the Unforgivable incantations.”

“Tom, focus,” Stella says, rolling her eyes.

“Yes,” he says, shaking himself a little. “Memory manipulation. Let’s go.”

“But it’s _late_ ,” Stella says, even as she gets up from the bed. “We can wait until tomorrow –”

“No we can’t,” Tom says, and when they reach the closed library they pull the doors open and silence the alarms with a spell they developed in fourth year.

“You’re the worst influence,” Stella says when they have a lamp burning at the far end of the library where nobody will see them and a pile of books on memory manipulation piled on top of each other so high that she can barely see the top of her brother’s head, and Tom laughs at her.

The arrival of the Christmas holidays means a reprieve from lessons, and a bunch of invitations from Tom’s boys for him to come to their houses; he turns them down and returns to the library with Stella, moaning about how difficult it is to be popular.

“Well, don’t be popular, then,” she shrugs at him. “I’m just fine.”

“You have me,” he says, and she doesn’t confirm or deny anything. “We need to go to the Ministry,” he says as they sit down. “It’ll be easy enough to go down to Hogsmeade and Apparate into the Ministry – we need access to their archives for this to work.”

Because Tom and Stella have a way of making things happen, they arrange to go down to Hogsmeade two days later, and then visit the Ministry of Magic instead, Tom Apparating the pair of them directly into the Atrium and then hanging back, letting Stella take the lead.

“Hello, mister,” she says to the bored-looking wizard behind the welcome desk, looking as angelic as possible, beaming up at him. He looks mildly interested in this, and judging by his overall demeanour this equates to his undivided attention. “My friend and I are meant to be looking into an internship in the archives, could you tell us where those are?”

“Sure thing, doll,” the man says, not even noticing that they don’t have badges on like everybody else in the Atrium, and Stella has to step on Tom’s foot to remind him to keep a cordial expression on his face while the man gives them an overly complicated set of directions, complete with unnecessary hand movements.

“You’re nobody’s _doll_ ,” Tom says, bristling once she’s cast a quick memory charm on the man just to cover their tracks and the two of them have made their escape.

“I know that,” Stella says peaceably, knowing that the best way to calm down is to not care. Tom grumbles a little more, but calms, just as she’d intended, and then they reach the archives and there is no more talking for several hours. “I think I found it,” Stella is the one to say, holding up a dusty tome which she thinks is mostly held together with hope.

“Excellent,” Tom says, looking up from his perusing of the records about the establishment of Azkaban. “D’you think they’d notice if a couple of these went missing?”

“There are probably spells on them,” Stella says. “I’m planning to duplicate this one and take the copy out.” Tom brightens.

“Oh, good idea,” he says, turning back to the shelves and starting to pick out the parts that he wants to peruse further. 

**xxx.**  
They only have to spend a few months in the orphanage every year, and it’s such a short time that it really shouldn’t seem as bad as it does, and it certainly shouldn’t compare to the eleven straight years they spent in the orphanage before they even knew Hogwarts existed, but – well. That was the problem. They hadn’t known Hogwarts had existed, and knowing that the rest of the world was just as grey and bleak as the orphanage hadn’t made their lives happier, exactly, but they’d been settled. Now, the knowledge of other places was in their minds – Hogwarts, Hogsmeade, even Muggle London outside Platform Nine and Three Quarters, all alive and vibrant and full of people who were actually living instead of just existing – it has slithered under their skin, into their bloodstream, threatening to vibrate out of them.

Blessed freedom for ten months, and then an abrupt, terrible return to the reality of their childhood home; Stella thinks, staring up at the ceiling at night, that this might be worse than an eleven-year existence, but then she thinks determinedly of Hogwarts and learning and knowledge at the tips of her fingers, and reminds herself that she wouldn’t give any of that up for the world.

“Well, maybe for the world,” Tom says teasingly when she tells him this.

Mrs Cole tsks loudly at their resolute silence and determined detachment from everyone, and decides that it would be far less trouble if she simply gives them a tiny room containing two mattresses and mostly leaves them to their own devices. It’s a small blessing, but a blessing nonetheless. They practice their magic there freely, and no notices come from the Ministry.

“We’ve done it,” Stella says idly, after forty-eight hours have passed since she cast a Warming Spell on their room.

“I told you we could,” Tom says, but he’s clearly distracted. “God, it’s like a chain,” he says, slumped on Stella’s bed and leaning on her. She thinks she can feel him petting her hair, but she’s not quite sure. “Can you feel it? It’s dragging us down.”

“Forty-two days left,” Stella tells him, glaring up at the cracked ceiling. When Hogwarts’ ceilings were cracked, it was quaint and charming; the cracks in this ceiling seem more like threats.

“My soul is being sucked out,” Tom groans. Stella considers giving his arm a consolatory pat, but decides that it would be altogether too much effort.

“I found something for you,” she says instead, rolling onto her side to face Tom. He mimics her so that they’re facing each other.

“Oh?” he asks. “And what’s that?”

“Well, I went into the records of the orphanage,” Stella says. “And then I used your middle name and the name Merope Gaunt our mother gave, and I did some research –”

Tom sits up straight, tiredness forgotten. “You _are_ a star,” he tells her. “And?”

“And there was a family under that name that lived in a small town near here,” she says. “The Gaunts. I have their address, too.”

Tom frowns at her, a little, and she laughs. “I said I’d join you, didn’t I?”

“You said you’d join me killing them,” he says. “Not finding them.”

“We have to find them to kill them,” Stella points out, and Tom nods. 

“We’ll go to the address tomorrow,” he promises, and this time it’s Stella who nods. She’d said that she didn’t care, but now that it was so close – well, she can’t help being curious. What blood did she come from? she wonders. Will she like it? “Actually, give me the address,” Tom says, almost a question but not quite, about as polite as he can get.

“No.”

“No?” Tom asks.

“No,” Stella repeats, and when Tom turns to look at her quizzically she raises an eyebrow. “Well, you have so much more incentive to make sure I stay alive this way.” Tom laughs at that, loud and long and happy.

“For one night?”

“I could make it several more, if we _really_ want to drag this out. We do have forty-two days of this place left, after all,” Stella says. Tom laughs again.

“I would keep you alive even if you weren’t my sister,” he promises, twining their fingers together. “You are the only one –” he pauses, and in the brief silence there is an _everything_ , implications that are too powerful to consider, so Tom lets the moonlight play off his shoulders as he shrugs. “The only one,” he says, and it’s enough.

After a pause, when she can tell by his breathing that he’s just about to go to sleep, Stella says, “Little Hangleton.”

“Little Hangleton,” Tom replies, sleepy, but she can hear the smile in his voice. Forever ago, she remembers thinking of the two of them, of the race that they are running, of how each of them has killed the other once. She remembers thinking of the words _one, inevitable, outcome_ , and then promptly ignoring them again, because in those words there are more implications that are far too great for her to consider. The thought refused to disappear, lurked over her shoulder in every interaction with her own brother like a dark shadow.

He thinks he’s won this bout, she thinks, staring at the ceiling as he goes to sleep properly. She thinks she’s won. Maybe it’s possible, then, for both of them to be happy.


End file.
